Related papers: Evidence for hc Production from psi-prime at CLEO
A precision measurement of the mass of the h_c(1P1) state of charmonium has been made using a sample of 24.5 million psi(2S) events produced in e+e- annihilation at CESR. The reaction used was psi(2S) -> pi0 h_c, pi0 -> gamma gamma, h_c ->…
The h_c(1P1) state of charmonium has been observed in the reaction \psi(2S) -> \pi0 h_c -> (\gamma\gamma)(\gamma\eta_c) using 3.08 million \psi(2S) decays recorded in the CLEO detector. Data have been analyzed both for the inclusive…
Results are presented on Charmonium using data collected with the CLEO III and CLEO-c detectors at the Psi(2S) and Psi(3770). Measurements include, the first observation of the hc(1P1) state, the electronic widths of the J/Psi and Psi(2S),…
The CLEO-c Experiment has made several recent contributions to the study of charmonium decays. This review briefly outlines the CLEO-c analyses of charmonium that were completed or made public during 2010. Special attention is given to the…
At CLEO, charmonium spectroscopy is pursued both thorugh e+e- annihilation data taken in the Upsilon region and more recently at psi(2S). A nmber of first observations (eta_c', h_c, pi and K form factors) have been made, and numerous high…
We report on the observation of the eta_{c}^{prime}(2^{1}S_{0}), the radial excitation of eta_{c}(1^{1}S_{0}) ground state of charmonium, in the two-photon fusion reaction gamma gamma rightarrow eta_{c}^{prime} rightarrow…
At CLEO, the charmonium singlet states eta_c(2 1S0) and h_c(1 1P1) have been firmly identified and a long standing discrepancy for Gamma_(gamma gamma)(chi_c2) has been resolved.
We present measurements of the charmonium state $h_c(^1P_1)$ made with 106M $\psi'$ events collected by BESIII at BEPCII. Clear signals are observed for $\psi'\to\pi^0 h_c$ with and without the subsequent radiative decay…
We report on the observation of the eta_c^' (2 ^1S_0), the radial excitation of eta_c (1 ^1S_0) ground state of charmonium, in the two-photon fusion reaction gamma gamma to eta_c^' to K_S^0 K^{\pm} pi^{\mp} in 13.4 fb^{-1} of CLEO II/II.V…
We report a new analysis of double charmonium production in e+ e- annihilation using a data sample collected by the Belle experiment. We confirm our previous observation of the processes e+ e- -> J/psi eta_c (chi_c0, eta_c(2S)) and perform…
We suggest searching for excited charmonium states in $e^+e^-$ annihilation via double charmonium production at $\sqrt{s}=10.6$ GeV with $B$ factories, based on a more complete leading order calculation including both QCD and QED…
Recent results from BES and CLEOc experiments on charmonium decays using J/psi, psi' and psi'' data samples collected in e+e- annihilation are reviewed, including the measurement of the relative phase between strong and electromagnetic…
We present a new analysis of double charmonium production in e^+ e^- annihilation. The observation of the processes e^+ e^- -> J/psi eta_c, J/psi chi_c0, and J/psi eta_c(2S) is confirmed using a dataset more than three times larger than…
Using data acquired with the CLEO-c detector at the CESR e+e- collider, we measure branching fractions for J/psi, psi(2S), and psi(3770) decays to gamma pi0, gamma eta, and gamma eta'. Defining R_n = B[ psi(nS)-->gamma eta ]/B[…
Using a sample of 2.59 x 10^7$ psi(2S) decays collected by the CLEO--c detector, we present results of a search for the decay chain psi(2S) -> pi^0 h_c, h_c -> n(pi^+ pi^-) pi^0, n=1,2,3. We observe no significant signals for n=1 and n=3…
We report the latest outcomes for the Charmonium system investigation on 226x10^6 J/Psi and 106x10^6 Psi' events collected with the BESIII detector at the BEPCII e+e- collider.
We study the direct production of the $J^{PC}=1^{++}$ charmonium state $\chi_{c1}(1P)$ in electron-positron annihilation by carrying out an energy scan around the mass of the $\chi_{c1}(1P)$. The data were collected with the BESIII detector…
Recent experimental results on charmonium $h_c(^1P_1)$, $\eta_c(1S)$ and $\eta_c(2S)$ from Belle, BaBar, CLEO and BESIII are reviewed. $h_c$ production and properties, the $\eta_c(1S)$ lineshape and the observation of $\eta_c(2S)$ in…
We suggest the ratio of the $\psi''(3770)/\psi'(3686)$ production cross sections as an unambiguous probe of the dominance of hard, point-like physics in charmonium production. If hard physics dominates the charmonium production the ratio :…
The ALICE Collaboration at the LHC has measured the J/$\psi$ and $\psi^{'}$ photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV. The charmonium is identified via its leptonic decay for events…